Method for making two compartment envelopes

ABSTRACT

This disclosure teaches a method for making two compartment envelopes each from a unitary sheet of paper. The sheet is provided with a rectangular back panel as well as side flaps, a front flap of less width than the back panel and a closure flap. A window is cut in the front flap and thereafter pressure sensitive adhesive is applied to a remote area of the closure flap as well as to the front flap about the window. Silicone coated release paper is applied over the adhesive on the closure flap and a patch of acetate film is applied to cover the window. The envelope is then gummed and folded side flap over side flap to define a first of the compartments and then front flap over side flaps to define a second of the compartments. The release paper permits the closure flap to be folded for convenient packaging. The front flap and the closure flap are folded along hinge lines and the side flaps extend beyond the hinge lines whereby the side flaps are doubled onto the back panel in folding of the front flap and the closure flap.

United States Patent 1191 Watson 1 1 METHOD FOR MAKING TWO COMPARTMENT ENVELOPES [75] Inventor: Charles S. Watson, Glen Ridge, NJ.

[73] Assignee: Berlin & Jones Company, Inc., East Rutherford, NJ.

[22] Filed: Dec. 14, 1973 [211 Appl. No.: 424,876

[451 Mar. 4, 1975 Primary E.\'aminerRoy Lake Assistant Examiner-James F. Coan Attorney, Agent, or FirmCharles E. Baxley, Esq.

1 1 ABSTRACT This disclosure teaches a method for making two compartment envelopes each from a unitary sheet of paper. The sheet is provided with a rectangular back panel as well as side flaps, a front flap of less width than the back panel and a closure flap. A window is cut in the front flap and thereafter pressure sensitive adhesive is applied to a remote area of the closure flap as well as to the front flap about the window. Silicone coated release paper is applied over the adhesive on the closure flap and a patch of acetate film is applied to cover the window. The envelope is then gummed and folded side flap over side flap to define a first of the compartments and then front flap over side flaps to define a second of the compartments. The release paper permits the closure flap to be folded for convenient packaging. The front flap and the closure flap are folded along hinge lines and the side flaps extend beyond the hinge lines whereby the side flaps are doubled onto the back panel in folding of the front flap and the closure flap.

4 Claims, 6 Drawing Figures PATENTEU 4|975 SHEET 2 Bf 2 METHOD FOR MAKING TWO COMPARTMENT ENVELOPES BACKGROUND OF INVENTION This disclosure relates to an improvement in manufacturing two compartment envelopes. US. Pat. No. 3,116,010 disclosed an envelope having two comparb ments and made from a unitary sheet of paper. Two compartment envelopes are used regularly when for example it is desired to send mail of two different classes in one envelope. Present postal regulations permit affixing a first class letter to a package or envelope containing material mailed by another postal class. People make use of this technique for such purposes as sending letters and stock proxy forms (by first class mail) in conjunction with annual reports or other printed material (by third class mail), or for sending printed materials or items of merchandise in conjunction with a letter or a bill. Two compartment envelopes also are useful for mailing valuable documents such as stocks, bonds and the like in conjunction with a letter or address card.

Two compartment envelopes are difficult and expensive to manufacture and they have required substantial height for packaging, shipping and storage.

STATEMENT OF INVENTION The present disclosure permits manufacture of two compartment envelopes in a particularly useful, novel, unobvious and facile manner. A unitary sheet of paper is provided with a rectangular back panel as well as side flaps, a front flap of less width than the back panel and a closure flap. In one continuous path on an envelope machine (such as a Winkler 141, Mach V) a window is cut in the front flap and a pressure sensitive adhesive is applied both to a remote area of the closure flap and to the front flap about the window. Then a silicone coated release paper is applied over the adhesive on the closure flap and a patch of acetate film is applied over the window. The envelope is then gummed and folded side flap over side flap to define a first of the compartments and then front flap over side flaps to define a second of the compartments. The release paper permits the closure flap to be folded onto the front flap for convenient packaging, shipping and storing. When the envelope is put into use, the release paper is removed and the pressure sensitive adhesive on the closure flap adheres to the front flap to seal both the first and the second compartments.

Accordingly one object of this invention is to provide a method for making two compartment envelopes of the character stated which method requires only one pass on an envelope machine, such as a Winkler 141, Mach V.

Another object of this invention is to use a single application of pressure sensitive adhesive for both the acetate window cover on the front flap and the release paper on the remote area of the closure flap.

Still another object of this invention is to reduce height requirements for packaging, shipping and storing two compartment envelopes.

Still another object of this invention is to provide a sturdy, secure two compartment envelope.

Still another object of this invention is to reduce costs involved in making two compartment envelopes.

DESCRIPTION OF DRAWINGS The foregoing and other objects, features and advantages of this method will appear more fully from a following detailed description of a preferred embodiment and from claims which also follow all viewed in conjunction with accompanying drawings wherein:

FIG. 1, extended to FIG. 1A, is an idealized side elevation view of an envelope machine adapted to carry out the method of this invention.

FIG. 2, extended to FIG. 2A, is an idealized plan view of the envelope machine shown in FIG. 1 extended to FIG. 1A.

FIG. 3 is a plan view of an envelope showing locations of areas to which adhesive is applied.

FIG. 4 is a perspective view showing a finished two compartment envelope made in accordance with this invention and ready or shipment.

DESCRIPTION OF PREFERRED EMBODIMENT As seen best from FIGS. 2 and 3 a unitary sheet of paper 11 is scored to provide fold lines which define a rectangular back panel 12, two side flaps l3 and 14 which are respectively hinged to the back panel 12 along hinge lines 15 and 16, a front flap 17 which is hinged to the back panel 12 along a hinge line 18, and a closure flap 19 which is hinged to the back panel 12 along a hinge line 21.

The envelope machine shown in FIGS. 1, 1A, 2 and 2A is ofa known design, such as a Winkler l4l, Mach V, and the envelope machine is adapted specially to carry out the method of this invention. Details of the envelope machine are familiar to those skilled in this art, so no elaboration thereon is considered necessary here.

The scored sheets 11 are fed to the envelope machine by means of a feed mechanism 22 and folded envelopes 23 ready for shipment are delivered at a discharge station 24. The scored sheets 22 are delivered one at a time with their inward sides 25 facing upwardly to a printing station 26 whereat ink is printed onto their outward sides 27. Such printing generally includes decorations, instructions, titles or the like. All of the printing can be attended to on the outward sides 27 of the sheets 11.

From the print station 26 the sheets 11 are delivered one at a time to a panel cutting station 28 whereat, as shown in FIG. 2, a die cuts a window opening 29 out of the front flap 17. After the panel cutting station 28 the sheet 11 passes to a first gumming station 31 whereat pressure sensitive adhesive is applied to a remote area 32 of the closure flap l9 and to a margin 33 of the front flap 17 which margin surrounds the window opening 29.

At a patching station 34 a patch 35, preferably of ac etate film, is applied over the window opening 29 and in contact with the gummed area 33 on the front flap 17. Also another patch 36 of release paper, preferably silicone coated, is applied over the gummed area 32 of the closure flap 19.

From the patching station 34 the sheet 11 passes longitudinally under the envelope machine for its entire length (and the sheet 11 may be heated during such passage 37 to assume complete drying of the ink). Thereafter the sheet 11 emerges again to the upper level of the envelope machine where it is delivered to a series of gumming and folding stations 38, 39, 41, 42

and 43. At station 38 gum is applied to a remote margin 44 of the side flap l3 and thereafter at station 39 the side flaps l3, 14 are folded against the inward side 25 of the back panel 12 with the ungummed side flap l4 overlapped by the gummed side flap 13 to define a first compartment 45. Thereafter gum is applied at station 41 to a proximal margin 46 as well as lateral margins 47 and 48 of the front flap 17 and then the front flap 17 is folded at station 42 against the side flaps 13, 14 to define a second compartment 49. The closure flap 19 is folded at the station 43 onto the front flap 17.

It will be apparent to those skilled in manufacture of envelopes that various deviations can be made from the described preferred embodiment of the invention without departing from a main theme of invention which is set forth in claims which follow.

I claim:

1. A method for making a two compartment envelope from a unitary sheet of paper having an inward side and an outward side and having a rectangular back, a first and a second side flap each hinged on opposite edges of and foldable against the inward side of the back panel and overlappable to form a first compartment, a front flap of less width than the back panel and hinged on a remaining edge of the back panel and foldable against the side flaps to form a second compartment, a forth edge hinged to a closure flap which folds over into contact with the front panel to enclose both the first and the second compartments, the method comprising steps of:

advancing the sheet open with the inward side upward along a continuous path,

printing with ink on the outward side of the sheet,

die cutting a window in the front flap,

applying pressure sensitive adhesive to the closure flap and to a margin of the front flap about the window,

applying a strip of a release paper over the adhesive on the closure flap,

applying a patch of a transparent film over the window and in contact with the adhesive on the front flap,

drying the ink,

applying gum to a remote margin of one of the side flaps,

folding the side flaps against the inward side of the back panel with the ungummed flap overlapped by the gummed flap to define a first of the compartments,

applying gum to a proximal margin and to lateral margins of the front flap,

folding the front flap against the side flaps to define a second of the compartments, folding the closure flap against the front panel.

2. The method of claim 1 and the front flap and the closure flap folded along hinge lines,

the side flaps extending beyond the hinge lines whereby the side flaps are doubled onto the back panel both on the folding of the front flap and the closure flaps.

3. The method of claim 2 with the patch being acetate.

4. The method of claim 3 with the release paper being silicone coated. 

1. A method for making a two compartment envelope from a unitary sheet of paper having an inward side and an outward side and having a rectangular back, a first and a second side flap each hinged on opposite edges of and foldable against the inward side of the back panel and overlappable to form a first compartment, a front flap of less width than the back panel and hinged on a remaining edge of the back panel and foldable against the side flaps to form a second compartment, a forth edge hinged to a closure flap which folds over into contact with the front panel to enclose both the first and the second compartments, the method comprising steps of: advancing the sheet open with the inward side upward along a continuous path, printing with ink on the outward side of the sheet, die cutting a window in the front flap, applying pressure sensitive adhesive to the closure flap and to a margin of the front flap about the window, applying a strip of a release paper over the adhesive on the closure flap, applying a patch of a transparent film over the window and in contact with the adhesive on the front flap, drying the ink, applying gum to a remote margin of one of the side flaps, folding the side flaps against the inward side of the back panel with the ungummed flap overlapped by the gummed flap to define a first of the compartments, applying gum to a proximal margin and to lateral margins of the front flap, folding the front flap against the side flaps to define a second of the compartments, folding the closure flap against the front panel.
 2. The method of claim 1 and the front flap and the closure flap folded along hinge lines, the side flaps extending beyond the hinge lines whereby the side flaps are doubled onto the back panel both on the folding of the front flap and the closure flaps.
 3. The method of claim 2 with the patch being acetate.
 4. The method of claim 3 with the release paper being silicone coated. 